As world coral reefs suffer fourth global albinism eventHeat stress is building up in the Caribbean even earlier than 2023, which was a record year for the region, according to data released Thursday by the National Oceanic and Atmospheric Administration.
“I hate that I have to keep using the word ‘unprecedented,'” said Derek Manzello, coordinator of the agency’s Reef Watch program. “But again this year we are seeing unprecedented patterns.”
Scientists hope that conditions will ease as the natural El Niño weather pattern associated with rising ocean temperatures recedes. Officials say conditions are quickly transitioning to neutral conditions, with a cooler La Niña expected this summer or fall.
But now, temperatures in the Caribbean near Panama, Costa Rica, Nicaragua and Colombia are reaching levels not seen for weeks, an ominous sign. Heat destroys coral reefs across region last year. Scientists say they are still determining the scale of deaths caused by last year’s bleaching. A Research on coral reefs near Huatulco, Oaxaca, Mexicofound that coral mortality ranged from 50% to 93%, depending on the reef area.
Bleaching occurs when stress causes corals to lose the symbiotic algae that help nourish them. While corals can survive periods of bleaching, prolonged or repeated bleaching may kill these critters. Even those who initially recover may succumb to the disease within the next year or two.
While various stressors can cause coral bleaching, including pollution or changes in salinity, the four recorded global bleaching events since 1998 have all been caused by rising ocean temperatures.Researchers estimate the world has lost Half of the coral cover Since 1950.
Coral reefs are sometimes called marine rainforests because they support tremendous biodiversity. A quarter of all marine species depend on coral reefs at some stage of their life cycles, and they also protect coasts from storms.
The fourth global bleaching event has been intensifying since early 2023, with at least 62 countries and regions experiencing bleaching phenomena. Last summer in the Florida Keys, Scientists race to preserve endangered coral samples. The Great Barrier Reef off Australia has taken a heavy toll in recent months. Dr Manzello said researchers in Brazil were currently documenting the worst bleaching in the country’s history.
The fourth global bleaching event is already the most widespread in 365 days, with 60% of coral reef areas experiencing bleaching-level heat stress. In the Atlantic, the figure was 99.7%, officials said.
Last month was the hottest April on Earth’s record, with global average temperatures breaking all historical records for the year for 11 consecutive months.
Dr Manzello said climate change was the “building block” for extreme ocean temperatures, but the current peak was even more obvious exceeds scientists’ expectations for human-induced global warming. Natural El Niño weather patterns exacerbate the heat. Scientists also want to know whether the extra heat comes from a knock-on effect from reduced shipping pollution, or from the eruption of an underwater volcano in 2022.
Raymond Chung Contributed reporting.
